Automatic machine tool for working elongated material in increments

ABSTRACT

Automatic lathe for working elongated material in increments. The lathe has a feed head at one end, a head stock intermediate its ends carrying rotating cutting tools and a collet for holding the material from rotation, a tail stock spaced in advance of the head stock and having gripping jaws conforming to and gripping the formed material for severing by a cutoff tool. The feed head grips and advances the material along the head stock and tail stock. The cutting tools carried by the head stock rotate about the material and form an increment of the material in a single forming operation. The tail stock carries gripping jaws movable inwardly in parallel planes in synchronism to grip and hold the material from rotation for the cutting off of a complete article. A second tail stock having gripping jaws may be spaced in advance of the first tail stock, to cooperate with the jaws in the first tail stock to further hold the material during a severing operation.

United States Patent Horst E. Eisenhardt Weinsbcrg, Germany [21] Appl.No. 832,087

[22] Filed June 11, 1969 [45] Patented Aug. 3, 1971 [73] AssigneeConver-Maschinenbau Gmhlll & Co. KG

[72] Inventor [54] AUTOMATIC MACHINE TOOL FOR WORKING ELONGATED MATERIALIN INCREMENTS 3,381,558 5/l968 Eisenhardt ABSTRACT: Automatic lathe forworking elongated material in increments. The lathe has a feed head atone end, a head stock intermediate its ends carrying rotating cuttingtools and a collet for holding the material from rotation, a tail stockspaced in advance of the head stock and having gripping jaws conformingto and gripping the formed material for severing by a cutoff tool. Thefeed head grips and advances the material along the head stock and tailstock. The cutting tools carried by the head stock rotate about thematerial and form an increment of the material in a single formingoperation. The tail stock carries gripping jaws movable inwardly inparallel planes in synchronism to grip and hold the material fromrotation for the cutting off of a complete article, A second tail stockhaving gripping jaws may be spaced in advance of the first tail stock,to cooperate with the jaws in the first tail stock to further hold thematerial during a severing operation.

PMENTEMUB BIB?! 3,595,545

SHEET i111? 0F 3 FIG. 3

JNVENTOR.

PMENTEU M18 31% 3,596,545

SHEET 3 OF 3 AUTOMATIIC MACll-llliNlli 'llOOlL liOh WOhllillNGlELONlGA'lllElD MA'lllEiillAL llN iNiClilEMllEN'lS SUMMARY AND OBJECTSOF THE INVENTION Forming lathe for elongated material in which thematerial is held stationary during the forming operation in whichclamping jaws in advance of the forming tools are mounted for parallelmovement symmetrically of the material the same distances, andconforming to the formed material for holding the material during anoperation of severing or effecting an additional forming operation onthe material in advance of the head stock.

A principal object of the present invention is to provide a simple andimproved form of forming lathe arranged with a view toward holdingmaterial stationary during a forming and severing operation on thematerial, and arranged with a view toward rigidly gripping the formedmaterial without deforming the material, to accommodate ready severingof the material.

A further object of the invention is to provide a simplified form offorming lathe for working elongated rod or bar stock, arranged with aview toward advancing the material for a forming and severing operationand holding the material in accurately aligned relation for its entirelength, during the forming and severing operation thereof.

Still another object of the invention is to provide an improved form offorming lathe for forming elongated bar stock, in which a collet chuckholds the stock in position during the forming operation thereof andclamping jaws having clamping surfaces conforming to the form of theformed material are spaced in advance of the collet chuck and move insynchronism to symmetrically grip and hold the material for severing.

Other objects, features and advantages of the invention will be readilyapparent from the following description of certain preferred embodimentsthereof, taken in conjunction with the accompanying drawings, althoughother variations and modifications may be effected without departingfrom the spirit and scope of the novel concepts of the disclosure.

DESCRIPTION OF THE DRAWINGS FIG. l is a plan view of an automaticforming lathe constructed in accordance with the principles of thepresent invention with certain parts shown in diagrammatic form andcertain other parts broken away and in section.

FIG. 2 is a fragmentary view in side elevation of the forming latheshown in H6. l, with certain parts broken away and certain other partsshown in vertical longitudinal section.

FIG. 3 is a partial fragmentary transverse sectional view takensubstantially along line Ill-ill of HG. 2, with the forming toolsremoved.

FIG. 4 is a partial fragmentary horizontal sectional view takensubstantially along line IV-IV of FIG, 3.

FIG, 5 is an enlarged partial fragmentary sectional views of the headstock and the tail stock and taken substantially along line V-V of HO.2; and

FIG. 6 is a view somewhat similar to FIG. 5, but illustrating a modifiedform in which the invention may be embodied.

DESCRllPTION Of PREFERRED EMlBODlll/IIENTS OF lNVENTlON In theembodiment of the invention illustrated in the drawings, [have shown inFIGS. l and 2 an automatic lathe in the form of an elongated boxlikeframe ll having a flat generally horizontal top or bed lid. The bed informs a mounting for a feel head 2, disposed at the incoming or rear endof the frame, an aligned head stock 3 spaced in advance of the feedhead, a tail stock f in alignment with and spaced in advance of the headstock 3, a cutoff device 5 disposed forwardly of the tail stock d and anadditional machining device 6 (FIG. 1 A rod 7 to be machined by theforming lathe, may be advanced from left to right by movement of thefeed head along the bed la as it grips the rod through the head stock 3to perform a machining operation thereon, and through the tail stock il,holding the formed product for severing. While the material to be formedis herein termed a rod, it is readily apparent that it may be anelongated bar or of any other form that may be turned on a lathe.

Thefeed head 2 is shown in FIGS. 1 and 2 as guided for advancingmovements along the bed in by parallel guides 9,9 mounted on the top ofthe bed la and extending therealong for a short portion of the lengththereof. The guides 9,9 may be conventional dove tail guides to guideand hold the feed head in vertical and longitudinal alignment.

The feed head 2 is advanced along the guides 9 to advance the workpiece7 therewith by operation of a lever 10 pivoted to the frame llintermediate its ends, beneath the top of the bed la, on a pivot pinMia. The lever 10 may have a roller or boss lltlb at its upper endengageable within a vertical slot 10c formed in the feed head 2. Thelower end of the lever 10 has a follower 10c therein extending inwardlytherefrom along a camming slot or groove 11 formed in a drum 12, keyedor otherwise secured to a main drive shaft 13 The main drive shaft 113may be driven by a suitable motor (not shown) through a gear trainindicated generally by reference character 13a, or other suitable drivemechanism, at a speed to uniformly advance the feed head 2 along theguides 9 and thereby advance the rod 7 along the head stock 3 toaccommodate a machining operation to be performed thereon, as willhereinafter more clearly appear as the specification proceeds.

The camming groove Illl is so formed in the drum l2 and the drum 112 isdriven at such a speed as to uniformly advance the feed head 2 whilegripping the rod to be machined by operation of a collet chuck M, and tothen retract the feed head 2 along the rod to be machined upon releaseof said collet chuck, to position the feed head 2 into position to againad- .vance the rod for a next succeeding machining operation thereon.

The collet chuck id is partially shown in longitudinal section in FIG. 2and may be of a conventional form and operated by operation of a lever15 in a suitable manner, to grip the rod 7 as the feed head 2 moves in aforward direction along the guides 9, and to then release said rod toaccommodate return movement of said feed head 2. The collet chuck 14 isengaged and released by operation of the lever 15 pivoted beneath thetop of the table lla, intermediate its ends, on a pivot shaft 115a,extending longitudinally of the table. A cam 16 on the main drive shaft113 is provided to rock said lever about the axis of the shaft 15a andto engage and disengage the collet chuck 14 in a suitable manner.

The connection from the lever 15 to the collet chuck 14 may be a rackand splined connection (not shown), or may be of any other conventionalform so need not herein be shown or described.

The head stock 3 is shown in FIG. 5 as having a tool head 17 rotatablymounted therein for rotation about an axis coaxial of the axis of therod 7. The tool head 17 has a head portion 17a rotatably journaledwithin the head stock on bearings 17b and a sleevelike portion extendingrearwardly along said head stock and journaled within said head stock onbearings 17d. The tool head 17 forms a mounting for tool holders 18mounted on and extending forwardly of the enlarged diameter drumlikeportion 17a of said tool head, and extending forwardly therefrom, forrotation about horizontal axes llii extending parallel to thelongitudinal axis of the rod 7.

A gear 17 is keyed or otherwise secured to the sleevelike portion of thetool head between the bearings 17b and 1l7d and may be rotatably drivenfrom the main drive motor for the machine (not shown) through a suitablegear train, which may be of any conventional form, to attain a selectedspeed of the tool head, and is no part of the present invention so neednot herein be shown or described further.

Each tool holder m carries a forming tool 19 rotatable about the axis ofthe rod 7 by rotatable movement of the tool head 17, and held from axialmovement along said tool head, but fed or advanced radially toward therod 7, to effect a forming operation thereon. The tools 19 arepreferably formed to form the rod 7 to the required form throughout thelength of the portion of said rod in registry with said tool holders toeffeet the machining of a succession of complete articles along saidrod, each of which is machined in a single machining operation.

Pivotal movements of the tool holders 18 to maintain the tools 19 inproper relation to form the rod 7 to a desired form, may be controlledto maintain the two tools in cutting relation with respect to the rodand to feed the tools towards the rod to effect a forming operationthereon. Suitable cam means (not shown) may be provided in the interiorof the head stock 3. Said cam means may rotate with a housing 19',suitably mounted in said head stock, for rotation about the axis ofrotation of the tool head 17. The housing 19' may be driven from a gearwheel 19", driven from the main drive motor at a speed differing fromthe speed of the tool head 17, to maintain the tool holders 18 in thecorrect positions through the cam means, to hold the tools 19 to effecta cutting operation on the rod 7 as shown in FIG. 5, and to effectradial feed of said forming tools in a manner which need not herein beshown or described further since it forms no part of the presentinvention.

A collet-type holding fixture 20 in the form of a draw-in collet 20' isprovided to'rigidly hold the rod 7 during a form turning operationthereon. The draw-in collet 20 has a rearwardly facing inwardly taperedconical head, cooperation with a corresponding conical surface of aclamping sleeve 21 extending about the collet. The clamping sleeve 21 isguided in the tubular shell 22 and has a close sliding fit therewith.Said tubular shell 22 has a rear end portion threaded in a threaded boreprovided in the head stock 3 and locked in position as by a lock nut 23.This accommodates axis adjustment of the tubular shell 22 to conform tothe form of a workpiece to be produced and to effect engagement of therod 7 by the drawin collet 20 immediately b hind the turning tools 19.The shell 22 extends through the head stock at least as far as the frontface of the rotating tool head 17 (FIG. 6) and may extend beyond thisfront face as shown in FIG. 5, depending upon the form to be machinedonto the rod 7. The shell 22 is mounted within the tool head 17 be meansof a radially prestressed needle bearing 24 in the axial bore of thetool head 17.

A thrust tube 26 is mounted within the shell 22 for axial movementtherealong and has bearing engagement with a rear flanged portion of theclamping sleeve 21. The rear end of the thrust tube 26 extends into theinterior of a clamping force transmitter 8.

The clamping force transmitter 8 is not herein shown or described indetail since it forms no part of the present invention, but is soconstructed as to axially move the thrust sleeve 26 in a forwarddirection to grip the draw-in collet 20' with the rod 7. The clampingforce transmitter 8 is actuated in a direction to move the thrust sleeve26 in a forward direction in a conventional manner by operation of alever 27 pivoted to the frame 1 beneath the bed 1a on a pivot pin 27aextending longitudinally of the frame 1. The upper end of the lever 27forms an actuator for the force transmitter while the lower end of saidlever cooperates with the cam 28 on the main drive shaft 13. Inwardmovement of the upper end of the lever 27 is converted by the forcetransmitter 8 into rectilinear movement of the thrust tube 26 along anaxis coaxial with the axis of the rod 7, to effect gripping of thecollet 20 with the rod 7 to hold said rod rigid during machiningthereof. The clamping force transmitter 8 may be of any suitable formand for example may be in the form of a rack actuated by the lever 27 tomove transversely of the head stock 3, and meshing with a toothedsegment, which may act on the thrust tube 26 through helical splinedfaces (not shown) extending along the portion of said thrust tubeextending into the thrust transmitter 8.

In the embodiment of the invention illustrated in FIGS. 1 to 5, the tailstock 4 may comprise a basic element 29 guided for adjustable movementalong the bed 1a in a direction extending longitudinally of said bed, indove tail guides 30 and held in position by means of locking screws 31(FIG. 3). The basic element 29 has a flat top surface having twocomplementary chucking slides 32 guided for movement transversely ofsaid flat top surface and transversely of the top of the frame 1. The

slides 32 may have gibs 32a, 321 depending from opposite sides thereofand having guiding engagement with the top of the basic element 29 toretain said slides against movement longitudinally of said basic elementand the bed la of the frame I. The chucking slides 32, each have aclamping jaw 33 mounted on the top thereof and secured thereto as bymachine or cap screws 33a (FIG. 3).

As best shown in FIGS. 3 and 5, each clamping jaw 33 has an innerclamping profile corresponding exactly to the turned profile of the rod7, to be gripped by said clamping jaws. The clamping jaws 33 are alsomounted on the top of the basic element 29 for movement toward and fromeach other in synchronism in parallel diametrically opposed planes toextend around a portion of the periphery of the finished turned portionof the rod 7, and engage the finished turned portion of the rod with ahigh degree of force, even where the finished shape of the rod maydeviate from its original cylindrical shape.

The clamping jaws 33 are moved toward and from each other into grippingengagement with the finished turned portion of the rod, and into releaserelation with respect to said rod, by operation of a vertically movablechucking wedge 36, guided in the basic element 29 for movement up anddown relative to said basic element, under the control of a cam 41 andlever 39 (FIG. 3).

The chucking wedge 36 is shown in FIG. 4 as being of a double T-shapedcross section with the crosses of the T extending longitudinally of thebasic element 29 and at opposite outer end portions of said chuckingwedge. The chucking wedge 36, as shown in FIG. 4 engages alignedT-shaped recesses 35 formed in the chucking slides 32. The T-shapedrecesses 35 converge toward the upper ends thereof and are of exactlythe same form as the crosses of the T's extending longitudinally of thebasic element 29 and bed la.

Thus, upward movement of the chucking wedge 36 will move the slides 32equal distances outwardly relative to the center of the rod 7 and willdisengage the clamping jaws 33 from the rod 7, to accommodate advance ofthe rod along the bed 1a for a next succeeding cutoff operation, asillustrated in FIGS. 1, 5 and 6. A spring 38 is seated in a downwardlyopening chamber formed in the basic element 29 at the upper end portionof said chamber and extends downwardly therefrom along a depending shank37, into engagement with a collar 38a secured to said depending shank 37as by a snap ring 3812. The spring 38 thus biases the lower end of theshank 37 into engagement with an upwardly facing engaging end portion ofa lever 39 and draws the clamping jaws 33 inwardly toward each other togrip the rod 7, under control of the lever 39, to accommodate thecutting off of a finished end portion of said rod. The clamping wedge 36is moved in an upward direction .by operation of the lever arm 39 andcam 41, engaging a follower 40 on the lower end of said lever arm toeffect separation of the clamping jaws 33 to release the rod. The cam 41may be keyed or otherwise secured to the main drive shaft 13 to berotatably driven therefrom.

The arrangement of the chucking wedges 36 and T-shaped recesses 35 arethus such that the clamping jaws move simultaneously equal distances ingripping or release directions relative to the axis of rotation of therotating tool head 17 and in coincident parallel planes to rigidly gripthe finished surface of the rod and hold the rod for cutting off withoutchattering.

The cutoff 5 comprises a basic housing element 42 guided in paralleldove tail guides 43 extending longitudinally along the bed In, toaccommodate the positioning of a cutoff saw 46 or any other conventionalcutoff tool into position to sever the finished product. Clamping screws44, shown as being threaded through the outermost dove tail guide 43,are provided to hold the basic element 4th in the required position ofadjustment.

Mounted on the basic element 42 for angular movement with respectthereto, is a swing arm 55 arranged to pivot about an axis extendinglongitudinally of the bed Ila to bring the saw as downwardly to cutoffthe machined rod and to raise said saw into position to accommodate therod to be advanced a length equal to the length of the machined piece toeffect a next succeeding cutoff operation of the rod. The saw III isshown as being a circular saw rotatably mounted on the end of the arm d5for free rotation with respect thereto in a conventional manner. A motor47 is shown as being secured to the forward end portion of the basicelement d2 (IFIGS. I and 2) in a suitable manner and may have drivingconnection with gearing contained within the basic element 42 fordriving the circular saw an about its axis through a suitable driveconnection extending along the arm 45, which may be a conventionalV-belt drive.

The arm M is moved about an axis parallel to the axis of the rod 7 tobring the saw as into and out of cutoff engagement with the rod 7 bymeans of a lever arm dd secured to the inner end of the arm 95 anddepending therefrom through an opening in the bed la. The lever arm Mhas a follower wheel 50 freely mounted on its lower end and bearingagainst the face of a cam 51, suitably secured to the main drive shaftI3, to be rotatably driven therefrom. A compression spring d9, seated atone end on the inside of a sidewall of the frame I is seated on itsopposite side on the outer side of the lever as, to bias the follower 5hinto engagement with the cam face of the cam 5ll.

As shown in FIG. 5, the circular saw extends within registering alignedslots 33c formed in the clamping jaws 33 forwardly of the clamping facesthereof during a cutoff operation thereof. The clamping jaws 33 thusgrip a finished workpiece rearwardly of the plane in which the workpieceis cutoff and behind a finished workpiece 7' and in front of a nextsucceeding workpiece 7".

In the embodiment of the invention illustrated in FIG. 6, I have shownclamping jaws 33 for gripping the material during a cutoff operation anda second set of clamping jaws 3d spaced forwardly of clamping jaws 33',for holding an advance workpiece '7" while the clamping jaws 33' haveclamping engagement with the forward end portion of a next succeedingworkpiece. The clamping jaws 33' are gripped with and released from theworkpiece in the same manner as the clamping jaws 33. The saw an isshown as being between the clamping jaws 33 and 35, for cutting the rearend of a workpiece 7' and the advance end of a workpiece 7 while the twoworkpieces are clamped in position by the two sets of clamping jaws 33'and 3d. The clamping jaws 3d are moved toward and from each other in thesame manner the clamping jaws 33 and are moved inwardly into grippingengagement with the material to be cut off, and outwardly to release thematerial, by a T-shaped wedge operated by a cam and leverage arrangement(not shown), operated from the main drive shaft 13. The wedge and camand leverage arrangement, therefore, need not herein be shown ordescribed since an undemtanding of the operation of the clamping jaws 33as shown in FIGS. 3 and 4, will give a complete understanding of theoperation of the clamping jaws 341. The fixture for the clamping jaws341 is also adjustable in a direction extending longitudinally of thematerial in the same manner as the clamping jaws 33 and 33', so adetailed description of the mounting for said clamping jaws need notherein be shown or described.

In the two forms of the invention illustrated in FIGS. 5 and 6, thecutting tools 113 on the rotating tool head are constructed to form theworkpiece between a front portion 7" and a rear portion 7" of theworkpiece as shown in FIG. 5. In FIG. 5, the workpiece 7" extends fromthe circular saw as rearwardly to a next separation point 52; where thecutting tools 19 have cut a groove in the workpiece. The workpiece 7"extends from this groove as far as the next rearwardly spaced cutoffpoint 52, in which region the material 7 has not yet been machined.

jaws for the rod.

In FIG. ll, an additional machining arrangement is shown, whichcomprises a working spindle 55 extending longitudinally of the axis ofthe workpiece '7 and in axial alignment therewith. The spindle 55 mayhave a thread cutting die 57 at its end, for cutting a male thread onthe front end of a leading workpiece 7'. The spindle 55 may be guidedand fed in an axial direction to advance the thread cutting die 57 alongthe workpiece '7' and may be rotatably driven by a motor 56 through asuitable gear train of any conventional construction, and not hereinshown or described since it forms no part of the present invention. Theadditional machining arrangement also may be adjustably moved along thetop of the bed plate In in conventional guides (not shown) and held inposition therein.

In FIG. II, a gripping device 55 is diagrammatically shown. The grippingdevice 55 is operable to come into gripping engagcment with theworkpiece 7 immediately after the workpiece has been given its malethread and after it has been cut off and released by the clamping jaws33 or the clamping jaws 33' and 34 as in the formof the inventionillustrated in FIG. 6, and transport the finished workpiece for furtheroperations thereon, and to thereby clear the front end of the bed plate,to accommodate the advance of a next succeeding workpiece to be given amale thread on its advance end, and to be cutoff along its rear end bythe saw 16.

I claim as my invention:

II. In an automatic machine tool,

a frame having a tope surface forming a bed plate,

a nonrotarywork holder mounted on said bed plate and adapted to grip andhold the material during a machining operation,

a rotary tool head rotatable about said work holder and carrying atleast one forming tool spaced in front of and closely adjacent said workholder,

clamping means spaced forwardly of said forming tool and adapted to gripthe formed material beyond a forming region thereof and including atleast two clamping jaws arranged symmetrically about the axis of theworkpiece,

means moving said clamping jaws toward and away from the workpiece alonga common plane,

a cutoff device movable toward and from the workpiece and spaced inadvance of said clamping jaws, to effect the operation of severing acompleted workpiece from one piece of elongated material closelyadjacent said clamping jaws,

additional clamping means spaced forwardly of said first mentionedclamping means and said cutoff device and including a pair of clampingjaws symmetrical about the longitudinal axis of the material, and

means moving said additional clamping jaws to come into grippingengagement with the formed material simultaneously with grippingengagement of said first mentioned clamping jaws along a common plane,to accommodate severing of the material between said clamping jaws.

h. In an automatic machine tool,

a frame having a top surface forming a bed plate,

a nonrotary work holder mounted on said bed plate and adapted to gripand hold the work during a machining operation,

a rotary tool head rotatable about said work holder and carrying atleast one forming tool spaced in front of and closely adjacent said workholder,

clamping means spaced forwardly of and closely adjacent said formingtool and adapted to grip the formed material beyond a forming regionthereof,

a cutoff device mounted on said bed plate for movement toward and fromthe workpiece and spaced in advance of said clamping means, to efiectthe operation of severing a completed workpiece from the piece ofelongated material closely adjacent said clamping means,

said clamping means including 'a support element mounted on said bedplate for adjustable movement along the axis of the formed material,

clamping jaws guided on said support element for movement in coincidentplanes into clamping engagement with the formed material,

said clamping jaws conforming to the form of the formed material,

and means moving said clamping jaws equal distances toward and away fromthe workpiece along a common plane.

3. An automatic machine tool in accordance with claim 2,

wherein registering transverse slots are formed in said clamping jaws inadvance of the clamping portions thereof,

wherein the cutoff device is a circular saw, and

wherein means are provided for moving said circular saw into said slotsto effect a cutoff operation of the formed material.

4. An automatic machine tool in accordance with claim 2, in which a slotand wedging arrangement is provided to synchronously move said clampingjaws into and out of engagement with the formed material, and includesT-shaped wedging slots in said clamping jaws and a T-shaped wedgeengaging said slots and moved up and down relative thereto.

5. An automatic machine tool in accordance with claim 4, wherein springmeans bias said T-shaped wedge to bring said clamping jaws into clampingengagement with the formed material.

6. An automatic machine tool in accordance with claim 1, including ahead stock carrying said nonrotary work holder, wherein the nonrotarywork holder includes a tube axially movable along said head stock andencircling the material to be formed, a draw-in collet coaxial with andextending forwardly of said tube, and a clamping sleeve extending aboutsaid draw-in collet and engaged by said tube and axially moved by saidtube to bring said collet into gripping engagement with the materialimmediately rearwardly of said forming tool. 7

7. An automatic machine tool in accordance with claim 1, including afeed head mounted on said bed plate rearwardly of said work holder,

a head stock forming a support for said rotary tool head and spaced inadvance of said feed head,

collet gripping means carried by said feed head,

means operable to bring said gripping means into and out of grippingengagement with the material to be machined,

other means advancing said feed head along said bed plate along the axisof the material to be machined, for advancing the material along saidnonrotary work holder and tool head,

wherein the nonrotary work holder is in the form of a collet work holderencircling and engageable with the material to be machined,

wherein means are provided for bringing said collet into grippingengagement with the material to be machined to hold the materialstationary during a machining operation thereon,

wherein other means are provided to move the clamping jaws insynchronism with each other,

wherein the cutofi device is in the form of a circular saw,

wherein means are provided for moving said circular saw to effect acutoff operation on two aligned pieces of formed material along the rearend of one piece and forward end of the next succeeding piece, and

wherein a common drive shaft is provided, and individual cam and levermeans are operated by said shaft for bringing said collet in said feedhead into gripping engagement with the formed material and for advancingsaid feed head along said bed plate, for bringing said nonrotary workholder into gripping engagement with the material during the performingof the machining operation thereon, for moving said clamping jaws insynchronism with each other equal distances into and out of clampingengagement with the formed material along diametrical planesintersecting the axis of the formed material and for bringing saidcutoff saw into and out of cutting engagement with the formed material.

8. An automatic machine tool in accordance with claim 2, in which theforming tool rotates about the material to be formed and is advancedradially inwardly toward the material to effect a forming operation onthe material and is held from axial movement relative to the materialand is formed to completely machine at least a length of the materialand an incision for registry with the cutofi device to effect severingof a workpiece while held by the clamping jaws.

9. An automatic machine tool in accordance with claim 8, in which theclamping jaws are shaped to conform to conform to the circumferentialsurface of the machined workpiece and rigidly hold the workpiece for acutoff operation.

UNITED STATES PATENT OFFICE CERTEFICATE 0F CORRECTION Patent No. 3, 596,545 Dated August 3, 1971 Inventofls) Horst E. Eisenhardt It is certifiedthat error appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

Column 1, line 56, change "views" to --view-; Column 1, line 69, change"feel" to --feed-.

Column 2, line 8, change "movements" to --movement--.

Column 3, line 36, change "axis" to "axial"; Column 3, line 44, change"be" to -by.

Column 4, line 7, change "321" to --32a--.

Column 6, claim 1., line 38, change "rope" to --top-.

Column 8, claim 9, line 45, after "to conform", delete second "toconform".

Signed and sealed this 25th day of April 1972.

(SEAL) Attest:

EDE'JAHD MJPLETCHER, JR. ROBERT GOTTSCHALK ."l ,tes'clng OfficerCommissioner of Patents

1. In an automatic machine tool, a frame having a tope surface forming abed plate, a nonrotary work holder mounted on said bed plate and adaptedto grip and hold the material during a machining operation, a rotarytool head rotatable about said work holder and carrying at least oneforming tool spaced in front of and closely adjacent said work holder,clamping means spaced forwardly of said forming tool and adapted to gripthe formed material beyond a forming region thereof and including atleast two clamping jaws arranged symmetrically about the axis of theworkpiece, means moving said clamping jaws toward and away from theworkpiece along a common plane, a cutoff device movable toward and fromthe workpiece and spaced in advance of said clamping jaws, to effect theoperation of severing a completed workpiece from one piece of elongatedmaterial closely adjacent said clamping jaws, additional clamping meansspaced forwardly of said first mentioned clamping means and said cutoffdevice and including a pair of clamping jaws symmetrical about thelongitudinal axis of the material, and means moving said additionalclamping jaws to come into gripping engagement with the formed materialsimultaneously with gripping engagement of said first mentioned clampingjaws along a common plane, to accommodate severing of the materialbetween said clamping jaws.
 2. In an automatic machine tool, a framehaving a top surface forming a bed plate, a nonrotary work holdermounted on said bed plate and adapted to grip and hold the work during amachining operation, a rotary tool head rotatable about said work holderand carrying at least one forming tool spaced in front of and closelyadjacent said work holder, clamping means spaced forwardly of andclosely adjacent said forming tool and adapted to grip the formedmaterial beyond a forming region thereof, a cutoff device mounted onsaid bed plate for movement toward and from the workpiece and spaced inadvance of said clamping means, to effect the operation of severing acompleted workpiece from the piece of elongated material closelyadjacent said clamping means, said clamping means including a supportelement mounted on said bed plate for adjustable movement along the axisof the formed material, clamping jaws guided on said support element formovement in coincident planes into clamping engagement with the formedmaterial, said clamping jaws conforming to the form of the formedmaterial, and means moving said clamping jaws equal distances toward andaway from the workpiece along a common plane.
 3. An automatic machinetool in accordance with claim 2, wherein registering transverse slotsare formed in said clamping jaws in advance of the clamping portionsthereof, wherein the cutoff device is a circular saw, and wherein meansare provided for moving said circular saw into said slots to effect acutoff operation of the formed material.
 4. An automatic machine tool inaccordance with claim 2, in which a slot and wedging arrangement isprovided to synchronously move said clamping jaws into and out ofengagement with the formed material, and includes T-shaped wedging slotsin said clamping jaws and a T-shaped wedge engaging said slots and movedup and down relative thereto.
 5. An automatic machine tool in accordancewith claim 4, wherein spring means bias said T-shaped wedge to bringsaid clamping jaws into clamping engagement with the formed mAterial. 6.An automatic machine tool in accordance with claim 1, including a headstock carrying said nonrotary work holder, wherein the nonrotary workholder includes a tube axially movable along said head stock andencircling the material to be formed, a draw-in collet coaxial with andextending forwardly of said tube, and a clamping sleeve extending aboutsaid draw-in collet and engaged by said tube and axially moved by saidtube to bring said collet into gripping engagement with the materialimmediately rearwardly of said forming tool.
 7. An automatic machinetool in accordance with claim 1, including a feed head mounted on saidbed plate rearwardly of said work holder, a head stock forming a supportfor said rotary tool head and spaced in advance of said feed head,collet gripping means carried by said feed head, means operable to bringsaid gripping means into and out of gripping engagement with thematerial to be machined, other means advancing said feed head along saidbed plate along the axis of the material to be machined, for advancingthe material along said nonrotary work holder and tool head, wherein thenonrotary work holder is in the form of a collet work holder encirclingand engageable with the material to be machined, wherein means areprovided for bringing said collet into gripping engagement with thematerial to be machined to hold the material stationary during amachining operation thereon, wherein other means are provided to movethe clamping jaws in synchronism with each other, wherein the cutoffdevice is in the form of a circular saw, wherein means are provided formoving said circular saw to effect a cutoff operation on two alignedpieces of formed material along the rear end of one piece and forwardend of the next succeeding piece, and wherein a common drive shaft isprovided, and individual cam and lever means are operated by said shaftfor bringing said collet in said feed head into gripping engagement withthe formed material and for advancing said feed head along said bedplate, for bringing said nonrotary work holder into gripping engagementwith the material during the performing of the machining operationthereon, for moving said clamping jaws in synchronism with each otherequal distances into and out of clamping engagement with the formedmaterial along diametrical planes intersecting the axis of the formedmaterial and for bringing said cutoff saw into and out of cuttingengagement with the formed material.
 8. An automatic machine tool inaccordance with claim 2, in which the forming tool rotates about thematerial to be formed and is advanced radially inwardly toward thematerial to effect a forming operation on the material and is held fromaxial movement relative to the material and is formed to completelymachine at least a length of the material and an incision for registrywith the cutoff device to effect severing of a workpiece while held bythe clamping jaws.
 9. An automatic machine tool in accordance with claim8, in which the clamping jaws are shaped to conform to conform to thecircumferential surface of the machined workpiece and rigidly hold theworkpiece for a cutoff operation.